Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| suppressor t cells regulate the cytolytic t lymphocyte response to syngeneic tumors induced by murine sarcoma virus (msv) in the mouse. | studies were designed to analyze the immune activities of spleen cells from mice previously injected with murine sarcoma virus (msv) and undergoing the processes of msv tumor growth and rejection. fractionation of msv-primed spleen cells according to cell size by velocity sedimentation at unit gravity showed that msv-specific cytolytic t lymphocytes (ctl) generated in vivo underwent an apparent transition in size from large to small cells as the tumor regressed. the majority of ctl precursors, h ... | 1979 | 156765 |
| an interferon-sensitive early step in the establishment of infection of murine cells by murine sarcoma/leukaemia virus. | nih 3t3 mouse cells were infected at very high multiplicity with murine sarcoma/leukaemia virus (msv/mlv) and then cloned. all of the 48 clones obtained were morphologically transformed, all but one showed anchorage-independence of growth, typical of msv-transformed nih 3t3 cells and most (91%) produced msv/mlv. when cells which had been pre-treated with 10(4) units/ml of purified interferon (if) were infected under the same conditions and then cloned in the presence of the same amount of if, on ... | 1979 | 225416 |
| reversion of kirsten sarcoma virus transformed human cells: elimination of the sarcoma virus nucleotide sequences. | the virus-specific nucleotide sequences in the rna and dna of a kirsten mouse sarcoma virus (ki-msv)-transformed non-producer human osteosarcoma cell clone and two subclones of these cells that reverted to a normal phenotype have been analysed by hybridization of sarcoma virus-specific complementary dna (cdna) to cellular rna or dna. whereas the transformed clone had acquired de novo ki-msv sequences in the rna and dna of the cells, both the revertant cell lines seemed to have lost most or all o ... | 1979 | 225428 |
| p21 of kirsten murine sarcoma virus is thermolabile in a viral mutant temperature sensitive for the maintenance of transformation. | we have recently described an intracellular protein, p21, in nonproducer cells transformed by either the kirsten (ki-msv) or harvey (ha-msv) strain of murine sarcoma virus (shih et al., virology, in press). the p21 is phosphorylated and has been shown to be coded for by either ki-msv or ha-msv. in this report, we compare the thermal stability of the newly synthesized [35s]methionine-labeled p21 in cells transformed by the wild-type ki-msv or by a mutant of ki-msv (ts 371) which is temperature se ... | 1979 | 225570 |
| orthotopic bone induction at sites of moloney murine sarcoma virus inoculation in mice. | moloney murine sarcoma virus (m-msv) induces at the site of inoculation in newborn and adult mice and rats various types of sarcoma, including osteosarcoma. the induced tumours are fatal in newborn, whereas sarcomas developed in adult animals regress spontaneously. the regression is mediated mainly by a cellular response. we have now demonstrated that the presence of sarcomas induced by m-msv is a powerful stimulus for periosteal osteogenesis around tumour masses. orthotopically induced osteogen ... | 1979 | 225678 |
| cytolytic activity of macrophages isolated from primary murine sarcoma virus (msv)-induced tumors. | macrophages isolated from regressing or progressing tumors induced by murine sarcoma virus (msv) were tested for cytolytic activity in a 18-h 51cr release assay. macrophages from the tumors of mice injected 14 days earlier with stocks of msv-producing regressor or progressor tumors had comparable levels of cytotoxicity. however, macrophages from the progressively growing tumors, 50--65 days after the inoculation with the progressor virus, had lower levels of cytotoxicity than those from the regr ... | 1979 | 226482 |
| different rat-derived transforming retroviruses code for an immunologically related intracellular phosphoprotein. | kirsten sarcoma virus (ki-msv) and harvey sarcoma virus (ha-msv) are mouse-rat recombinant viruses that were originally isolated by experimental inoculation of rats with helper-independent mouse type c viruses. we have recently identified in cells transformed by ki-msv or ha-msv, a phosphoprotein, p21, coded for by ki-msv and ha-msv [shih, t.y., weeks, m.o., young, h.a. & scolnick, e.m. (1979) virology 95, in press]. the p21, which is not a virion structural protein, was identified with antisera ... | 1979 | 226970 |
| thermolabile protein kinase molecules in a temperature-sensitive murine sarcoma virus pseudotype. | murine sarcoma virus-associated protein kinases that bind to actin have been purified by affinity chromatography on actin coupled to sepharose. heat inactivation studies showed the presence of thermolabile enzyme activity in pseudotypes containing a temperature-sensitivity mutant of murine sarcoma virus (msv) but not in two independent wild-type msv pseudotypes. studies with sephadex g-75 column fractions showed that a low molecular weight form, approximately 15,000, is the major thermolabile ki ... | 1979 | 226971 |
| loss of proviral dna sequences in a revertant of kirsten sarcoma virus-transformed murine fibroblasts. | a previously described revertant cell line (k-balb sr1212), derived as a single cell clone from a clonal line of murine fibroblasts (k-balb) transformed by a nonproductive infection with the kirsten strain of murine sarcoma virus, has normal morphology and growth kinetics and, unlike the transformed parent cell line, lacks a sarcoma virus that can be rescued. we report here that this reversion correlates with low to undetectable levels of expression of cellular ki-msv-specific rna and a reductio ... | 1979 | 227995 |
| comparative study of different isolates of murine sarcoma virus. | the rna genomes of a variety of murine sarcoma viruses (msv) were compared by heteroduplex analysis. these viruses included the moloney-derived isolates 124-msv, m1-msv, m3-msv, ht1-msv, and np-msv and also two independent isolates, gazdar msv and 1712-msv. all of these viral genomes exhibited the acquired cellular sequences previously identified in 3124-msv and thought to be responsible for transformation and sarcomagenesis. the location of the acquired cellular sequences within the envelope ge ... | 1979 | 229256 |
| heteroduplex analysis of the rna of clone 3 moloney murine sarcoma virus. | heteroduplex analysis of the rna isolated from purified virions of clone 3 moloney murine sarcoma virus (m-msv) hybridized to cdna's from moloney murine leukemia virus (m-mlv) and clone 124 m-msv shows that the main physical component of clone 3 rna is missing all or most of the 1.5-kilobase (kb) clone 124 m-msv specific sequence denoted beta s (s. hu et al. cell 10:469--477, 1977). this sequence is either deleted in clone 3 rna or substituted by a very short (0.3-kilobase) sequence. in other re ... | 1979 | 229257 |
| antiviral and anticellular effects of interferon on the mouse embryonic cells transformed by viruses and/or chemical carcinogen. | the antiviral and anticellular activity of partially purified mouse interferon has been tested in cell lines transformed with simian virus 40 (meb-sv 40), mouse sarcoma virus (harvey strain) (meb-msv), and 20-methylcholanthrene (meb-mch), respectively. the transformed lines were derived from c3h mouse embryonic primary cells. it has been shown that the meb-msv cells were 10 to 50 times less sensitive to the antiviral effect of interferon than the meb-sv 40 or meb-mch cells. a 30% reduction of th ... | 1979 | 230678 |
| growth pattern of tumours in mice induced by murine moloney sarcoma-virus and sarcoma-virus-transformed cells. | transplantation of a moloney sarcoma-virus (msv-m)-transformed producer cell line (sac(+)) induced progressively or regressively growing tumours in mice. progressive growth always occurred after transplantation of an msv-m non-producer transformant (sac(-)), whereas the msv-m released from the producer cells (sac virus) always induced tumours which regressed. in contrast to the non-producer, the producer transformant sac(+) as well as sac virus induced a strong immune response, detected in vitro ... | 1979 | 230854 |
| supplemental arginine increases thymic cellularity in normal and murine sarcoma virus-inoculated mice and increases the resistance to murine sarcoma virus tumor. | arginine supplements were given to 6 week old cba mice beginning 3 days prior to inoculation with a murine sarcoma virus, the moloney sarcoma virus (msv). although the basal diet contained 1.8% arginine and was therefore not arginine-deficient, supplementation of the diet and the drinking water with 0.5% arginine hcl reduced tumor incidence, lengthened the latency period, decreased tumor size, and hastened tumor regression. arginine also increased thymic weight and cellularity in normal and in m ... | 1979 | 231121 |
| inhibition of murine sarcoma virus induced transformation in an adenovirus -- nrk system. | cell transformation induced by murine sarcoma virus (msv-m) is significantly inhibited (80--90%) in a clonal line of normal rat kidney (nrk) cells when they are infected with rat cell passaged adenovirus 12 (r-ad12). no inhibition is seen when r-ad12 is added simultaneously with, or 1 1/2 or 24 hr after, msv-m infection, suggesting that inhibition occurs most probably intracellularly. there is also a direct correlation between the extent of focus formation and the concentration of r-ad12 used. c ... | 1979 | 231569 |
| decrese of collagen biosynthesis ability of swiss 3t3 cells transformed with the murine sarcoma virus (msv). | 1979 | 232424 | |
| functional heterogeneity and t cell-dependent activation of macrophages from murine sarcoma virus (msv)-induced tumors. | in studies on the functional activity of macrophages isolated from murine sarcoma virus (msv)-induced tumors, we have found that these cells may suppress immune responses as well as act as effector cells against the tumor. previously, we reported that macrophages from the tumor could inhibit the antitumor response by suppressing proliferation-dependent immune functions. here, we demonstrate that macrophages can also suppress the production of migration inhibition factor (mif) and macrophage acti ... | 1979 | 232622 |
| moloney murine sarcoma virions synthesize full-genome-length double-stranded dna in vitro. | moloney murine sarcoma virus (msv) virions incubated under optimal conditions were shown to support extensive synthesis of double-stranded dna. the major product, a 5950-base-pair (6-kilobase-pair dna) double-stranded dna, was characterized by cleavage with restriction endonucleases and shown to contain a 600-nucleotide-long direct repeat at both ends of the msv genome. linear dna molecules made in vivo shortly after infection were compared to the linear double-stranded dna synthesized in vitro. ... | 1979 | 291003 |
| suppression of lymphokine production by macrophages infiltrating murine virus-induced tumors. | immune spleen cells from mice injected with murine sarcoma virus (msv) can produce migration inhibition factor (mif) in vitro after stimulation with intact tumor cells. we have now found that this effector function can be regulated by suppressor macrophages present in the tumor. the cells from the tumor (cft) exert a strong suppressive effect even after treatment with anti-thy 1.2 plus complement but lose this capacity if adherent or phagocytic cells are removed, suggesting that the macrophage i ... | 1979 | 314424 |
| [lymph node cell composition and dna content in their different lymphocyte populations in mice with tumor induced by murine moloney sarcoma virus]. | the ratio of t and b lymphocytes and dna content in population enriched by these cells were analysed in the lymph nodes of balb/c mice with progressively growing sarcomas induced by the msv moloney and in untreated mice. t lymphocyte enriched fractions have a higher dna content in comparison to fractions enriched with b lymphocytes. sarcoma development promotes a decrease in the relative number of macronucleolar lymphocytes and simultaneous decrease of micronucleolar ones in the lymph nodes, par ... | 1979 | 315243 |
| lack of t-cell mediated cytotoxicity in m-msv system depending on h-2 haplotypes. | the h-2 restriction phenomenon was evaluated with regard to the immune response to moloney sarcoma virus (m-msv)-induced tumours in the mouse. using an in vitro 51cr release assay the lytic activity of lymphocytes from m-msv immune strains of mice, including several h-2 recombinant strains, was determined on leukaemic cell lines originally induced in mice of different strains by neonatal infection with moloney leukaemia virus. in analogy with other experimental models, it was observed that a com ... | 1979 | 315438 |
| tumor-enhancing suppressor activator t cells in spleens and thymuses of tumor immune mice. | cells from the spleens and thymuses of balb/c mice whose moloney sarcoma virus (msv)-induced, primary sarcomas have regressed 2-3 months earlier ("msv regressors") or are in the process of regressing can, when adoptively transferred to syngeneic mice given msv at the age of 20 days, prevent the natural regression of the msv sarcomas in the recipient mice. the cells responsible for this tumor-enhancing effect express the thy 1 marker. they are not demonstrable in the thymuses of normal untreated ... | 1979 | 315560 |
| effect of anti-mouse type-1 interferon globulin on the evolution of moloney sarcoma virus induced disease in mice. | the prolonged administration of potent sheep anti-mouse type-1 interferon globulin (anti-if igg) had a marked potentiating effect on moloney sarcoma virus (msv) infection in mice. the extent of resistance to the msv-induced disease was age-related. in 4-week-old balb/c mice, anti-if igg consistently induced 70-80% mortality due to the progression of early or late tumours and erythroleukaemia, whereas mortality of control mice was significantly lower. the same effect was obtained in 1-year-old ba ... | 1979 | 316806 |
| molecular cloning of moloney murine sarcoma virus: arrangement of virus-related sequences within the normal mouse genome. | the unintegrated circular dna form of moloney murine sarcoma virus (msv) has been cloned in bacteriophage lambda. discrete deletions in the viral genome were shown to occur during propagation of recombinant phage in escherichia coli. heteroduplex and restriction enzyme analyses indicated the deletion of tandemly repeated sequences within certain of the cloned msv dna inserts. cloned msv dna was used to prepare a probe composed of its acquired cellular (src) sequences, shown previously to be nece ... | 1979 | 392518 |
| "sarc" sequence transcription in moloney sarcoma virus-transformed nonproducer cell lines. | (3)h-labeled complementary dna(sarc), complementary to the murine sarcoma virus (msv)-specific portion of the moloney msv (m-msv) genome, was prepared. m-msv-specific rna was then quantitated in the cytoplasm of several m-msv-transformed, non-virus-producing, clonal nih 3t3 cell lines. these lines, designated 71 n clones 5, 6, and 3, have been characterized previously by the degree to which they exhibit transformation properties and transcribe moloney murine leukemia virus-related rna (s. salzbe ... | 1979 | 430602 |
| characterization and properties of a protein kinase associated with murine sarcoma-leukemia virus (msv-mulv). endogenous phosphorylation of a unique p10 polypeptide. | 1979 | 454404 | |
| effects of anti-interferon serum on growth and regression of moloney sarcoma virus induced tumours in mice. | administration of sheep anti-mouse interferon serum or globulin to weanling balb/c mice infected with moloney sarcoma virus (msv) accelerated the growth of tumours at the site of virus inoculation, increased the number and size of tumours, and inhibited their regression. the outcome of the msv-induced disease after injection of anti-interferon globulin depended on the age of mice. the antigenic stimulation by normal sheep serum or globulin also enhanced the growth and mortality due to msv but to ... | 1979 | 525154 |
| immunochemical characterization of tumor-associated surface antigens on a moloney leukemia virus-lymphoma, mbl-2. | tumor-associated surface antigens (tasa) on a moloney leukemia virus (m-mulv)-induced lymphoma, mbl-2, in c57bl/6 mice (b6) were characterized. the surface proteins of mbl-2 cells were selectively radioiodinated and then extracted by nonidet p40. the solubilized materials were then reacted with a variety of antisera: monospecific antisera to murine leukemia viral proteins (anti-gp69/71, anti-p30, anti-p15, anti-p12 and anti-p10), sera from b6 which regressed murine sarcoma tumors induced by muri ... | 1979 | 528073 |
| phenotypic mixing between two primate oncoviruses. | phenotypic mixing between the primate oncoviruses hl23v and bev has been demonstrated to occur in doubly-infected bat lung (tb) cells with the production of hl23v(bev) pseudotype virus. the presence of the hl23v(bev) pseudotype permitted the host range for replication of hl23v to be extended to murine cells previously 'resistant' to hl23v replication due to a block at the level of virus penetration. expression of bev genetic information was observed in doubly-infected rat cells and also in mouse ... | 1979 | 569684 |
| effects of sodium butyrate on the membrane glycoconjugates of murine sarcoma virus-transformed rat cells. | the temporal relationship between butyrate-induced cellular flattening of murine sarcoma virus-transformed rat cells (msv-nrk) and alterations in certain surface-associated biochemical markers of transformation, e.g., surface glycopeptides, glycolipids, fibronectin, hexose uptake, and cell-substrate adhesion was examined. the induction of elevated levels of the ganglioside gm3 and of a gdla-like ganglioside were observed to precede or to parallel cellular flattening. likewise, enhanced incorpora ... | 1980 | 7380882 |
| cytochalasin b-induced multinucleation of human tumor and normal cell cultures. | twelve human cell cultures derived from tumors, normal tissues, and derivative cultures transformed by either a rna tumor virus or chemical carcinogen were examined for their response to cytochalasin b (cb) and the expression of this marker was correlated with growth in soft agar and saturation density in monolayer culture. cell lines derived from carcinoma of the bladder (t24 and rt4), kidney (caki-1), prostate (du 145), and breast (mcf-7) multinucleated when growth in cb-supplemented medium, w ... | 1980 | 7397790 |
| tumors induced by progressor sarcoma virus (moloney) in mice: growth in the presence of an immune response and isolation of autonomously growing cells. | courses of tumors, which had been induced in adult stu mice with a regressor and with a progressor strain of moloney sarcoma virus (msv-m) were followed and compared. all 73 tumors induced by the regressor strain of msv-m (r-msv-m) regressed and 181 of 183 tumors induced by a progressor strain (p-msv-m) grew progressively and killed their hosts between 16 and 171 days after infection. even after inoculation of about 4 ffu of p-msv-m tumor development may occur and lead to progressively growing t ... | 1980 | 7436738 |
| type i and type ii interferons: differential antiviral actions in transformed cells. | in transformed mouse embryo cells, type ii interferon had much less antiviral activity than type i interferon. in non-transformed cells, the two interferons had similar high activity, reversal of the phenotype of moloney sarcoma virus (msv) transformed cells by sodium butyrate restored their sensitivity to the antiviral action of type ii interferon. additional evidence for a role of the cytoskeletal network in the action of type ii interferon is that its antiviral effect is reduced by cytochalas ... | 1980 | 6155431 |
| restriction of the rat-specific rns sequences of ki-msv to the nucleus of dibutyryl cyclic amp-treated k-a31 cells. | the treatment of oncogenically transformed cells in culture, with dibutyryl cyclic amp (camp) has, in many cases, resulted in a general phenotypic change towards the normal state. a virus-specific gene product(s) is responsible for the transformation of cells by sarcoma viruses and it has been suggested that the src gene product may act through the alteration of camp levels. with these premises we have studied the effects of dibutyryl camp on cell growth and virus genome expression in a kirsten ... | 1980 | 6161990 |
| t cell-mediated immunity to oncornavirus-induced tumors. i. ly phenotype of precursor and effector cytolytic t lymphocytes. | regression of tumor induced by murine sarcoma virus (msv) is accompanied by the formation of specific cytolytic t lymphocytes (ctl). selection of t-cells sets by ly phenotype determination allows separation of t sets involved in the cytolytic reaction. after msv inoculation we demonstrate that a) ly123+ cells contain precursors of ctl, b) direct cytolysis is mainly mediated by ly23 cells, 3) cytolytic memory is divisible into "early" memory, carried by ly23 cells, and "late" memory, which revert ... | 1980 | 6243332 |
| properties of a normal mouse cell dna sequence (sarc) homologous to the src sequence of moloney sarcoma virus. | a 15.0-kilobase (kb) eco ri dna fragment from normal mouse balb/c genomic dna that contains sequences (sarc) homologous to the acquired cell sequences (src) of moloney sarcoma virus (msv) has been cloned in phage lambda. the sarc region (1.2 to 1.3 kb) of the 15.0-kb cell fragment is indistinguishable from the src region of two isolates of msv as judged by heteroduplex and restriction endonuclease analyses. the cellular sequences flanking sarc show no homology to other msv sequences. whereas clo ... | 1980 | 6243788 |
| envelope properties of murine sarcoma virus-zero (msv-z). | 1980 | 6243828 | |
| localization of the src gene product of the harvey strain of msv to plasma membrane of transformed cells by electron microscopic immunocytochemistry. | using electron microscopic immunocytochemistry, we have investigated the intracellular location of the src protein (p21) in cells transformed by the harvey strain of murine sarcoma virus (ha-msv). antibodies to p21 were derived from tumor-bearing rats inoculated with ha-nrk cells. the distribution of p21 in intracellular sites in mdck dog cells transformed by ha-msv was examined and quantified using a recently developed immunocytochemical technique. more than 95% of p21 was localized to the inne ... | 1980 | 6247068 |
| double transformation of indian muntjac cells by avian and murine sarcoma viruses. | avian sarcoma virus-transformed indian muntjac cells, sr-mm-1, formed foci by murine sarcoma-xenotropic murine leukemia virus complex [msv(x-mulv)] superinfection. the response of sr-mm-1 and parental normal indian muntjac mm-2k cells to msv(x-mulv) infection was compared. focus formation by msv(x-mulv) followed two-hit kinetics in mm-2k, but one-hit kinetics in sr-mm-1 cells. msv(x-mulv)-infected sr-mm-1 cells formed larger colonies than uninfected sr-mm-1 cells in soft agar, while no colony wa ... | 1980 | 6247523 |
| factors affecting responses to murine oncogenic viral infections. | silica specifically kills macrophages in vitro, and in vivo has been used as a method of determining the possible immunological or other roles of macrophages in a number of viral infections. in experiments reported here, injection of 30 or 50 mg silica i.p. increased the severity of the oncogenic effects of the murine sarcoma virus (msv) and friend virus (fv) in balb/c mice. unlike herpes simplex and coxsackie b-3 infections, however, passive transfer of adult macrophages to suckling mice did no ... | 1980 | 6248095 |
| identification and molecular cloning of moloney mouse sarcoma virus-specific sequences from uninfected mouse cells. | when uninfected mouse cell dna is cleaved with restriction endonuclease ecori, a dna fragment of 14.0 kilobases can be identified by hybridization to cloned dna containing sarcoma specific sequences of moloney mouse sarcoma virus (m-msvsrc). the cellular dna fragment contains the entire m-msvsrc specific sequences. the 14.0-kilobase ecori dna fragment was cloned in bacteriophage lambda. the sequence organization of a recombinant clone, lambda . mtx-1, was analyzed by restriction endonuclease map ... | 1980 | 6248858 |
| [paramagnetic centers during carcinognesis induced by an rna-containing virus]. | an esr method was used to investigate the metalloenzyme centres, characteristics of cell energetic and detoxicity systems of models of tumors induced by rna virus msv(m) as progressor and regressor of tumor development. different stages of esr signal formation and its reverse transformation centres that reflect relations between tumor and organism the iron--sulphur proteins proved to be the most important. | 1980 | 6249398 |
| increased cyclic amp content directly correlated with morphological transformation of cells infected with a temperature-sensitive mutant of mouse sarcoma virus. | normal rat kidney cells infected with a cold-sensitive mutant of mouse sarcoma virus [nrk(msv-lb)] morphologically transform when exposed to adenosine 3':5' cyclic monophosphate (camp) at the restrictive temperature. the camp-induced morphological changes occur rapidly and are reversible. agents capable of elevating endogenous levels of camp [prostaglandin e1 (pge1) and cholera toxin (ct)] induced morphological transformation of nrk(msv-lb) cells at the restrictive temperature that was concentra ... | 1980 | 6252097 |
| the isolation and characterization of a clonally related series of murine retrovirus-infected mouse cells. | starting with cloned nih 3t3 mouse cells we have isolated a series of related lines infected with the kirsten murine sarcoma/leukaemia (msv/mlv) virus complex. these lines exhibit all three possible infected cell phenotopes: (i) transformed msv/mlv producers; (ii) non-transformed mlv producers; (iii) transformed non-producers. we have also selected non-transformed revertants from one of the non-producer clones. this series of lines allows the study of the expression of the virus genome against a ... | 1980 | 6252284 |
| action of three species of propionibacteria (p. granulosum, p. acnes, p. avidum) on experimental tumor systems in mice. | the antitumor activity of three different species of propionibacteria (p. granulosum, p. avidum and p. acnes) against murine sarcoma 180 and moloney-sarcoma-virus-induced tumor (msv tumor) was investigated. all three propionibacteria injected intraperitoneally or intratumorally in multiple doses of 1 mg per mouse appeared to be effective regarding the retardation of growth and the stimulation of regression of sarcoma 180 in cfw mice. moreover, the application of propionibacteria significantly pr ... | 1980 | 6252722 |
| immunization against primary, transplanted and spontaneous murine leukaemia using a live moloney sarcoma virus vaccine. | the purpose of this study was to use an immunization protocol with moloney sarcoma virus (msv-m) as active immunogen against exogenous and endogenous leukaemia. the s.c. route was chosen since it offered advantages over the i.m. route: the primary sarcomas were smaller, the regression faster, there were fewer recurrences and there was good persistent immunity. strong protection was obtained against primary leukaemias induced by friend leukaemia virus (flv), moloney leukaemia virus (mlv), rausche ... | 1980 | 6252923 |
| the induction of immunoblastic t cell sarcomas by virus-transformed prothymocytes. | the ontogeny of thymus-dependent lymphoid tumors induced by murine sarcoma-murine leukemia virus (msv-mulv) was investigated. tumors that developed in spleens of infected mice 6 or more months after the injection of virus were diagnosed as immunoblastic t cell sarcomas. cells derived from the tumors and established as a continuous cell line expressed the thymus leukemia (tl), brain-associated theta (bat), and qa2 cell surface antigens but lacked either the ly 1 or ly 2, 3 mature t cell different ... | 1980 | 6254363 |
| multinucleation in the presence of cytochalasin b by rna tumor virus-transformed cells. | rna tumor virus-transformed cell cultures derived from rat, mouse, hamster, and mink were examined for their response to cytochalasin b (cb), and the expression of this marker was correlated with growth in soft agar and tumorigenicity in vivo. continuous cell lines transformed and chronically infected with moloney murine sarcoma-leukemia virus (m-msv-mulv) or kirsten murine sarcoma-leukemia virus were extensively multinucleated when treated with cb. similarly, nonproducer moloney murine sarcoma ... | 1980 | 6254645 |
| a non-virion surface antigen on moloney sarcoma virus-transformed non-producer and producer cells. | sera from stu mice bearing sarcomas induced by cells producing the moloney sarcoma-helper-virus (m-msv/mlv) complex were cytotoxic for these cells as well as for m-msv non-producer and m-mlv producer cells. analysis by polyacrylamide gel electrophoresis of 125i-labelled surface antigens immunoprecipitated with such sera revealed the virus envelope glycoprotein gp71 on the producer cells and an additional antigen of mol. wt 55 k on the m-msv-transformed producer and non-producer cells. this antig ... | 1980 | 6255072 |
| simian virus 40 and moloney-murine sarcoma virus infection of bona fide mouse epithelium. | moloney-murine sarcoma virus (moloney-msv) and simian virus 40 (sv40) were found to infect successfully pure cultures of epithelial cells established from mouse liver and mammary tissue. msv infection resulted in transient morphological foci with persistent production of infectious virus. sv40 infection produced detectable levels of virus-specific t antigen in the cells but morphological transformants were not observed. | 1980 | 6255079 |
| immunity to friend virus complex: analysis of protection with a sarcoma virus pseudotype. | to specify the mechanism whereby inoculation of sarcoma viruses protects against leukemia development by leukoviruses, several experiments were performed using friend virus complex (fvc) and msv-f, a sarcoma virus pseudotype prepared in vitro with fvc as source of the helper component. the sarcomatous lesions induced by msv-f were self-limited, irrespective of dose and route of inoculation and protected against the progressive, lethal erythroleukemia induced fy fvc. the sera of msv-f primed mice ... | 1980 | 6257197 |
| induction of immune reaction against rat embryonal carcinoma by activation of viral genome. | a cell line (f3/1) derived from a rat embryonal carcinoma, originally induced in fetectomized rats injected with msv, was found to be essentially non-immunogenic in a syngeneic host; the cells did not produce c-type virions. the msv genome could be rescued by superinfection of f3/1 cells with endogenous c-type mouse virus and the cells were converted in a producer line-f3/1-p. the produced virus was shown to be msv by its ability to induce focus formation in mouse fibroblasts. in contrast to its ... | 1980 | 6263807 |
| increased sensitivity of fibroblasts of skin from patients with adenomatosis coli and peutz-jegher's syndrome to transformation by murine sarcoma virus. | skin fibroblasts from family members of cases of adenomatosis coli (ac) and peutz-jegher's syndrome (pj) were examined for susceptibility to morphological transformation by moloney murine sarcoma virus (msv) of rate 78ai cells, which was found in the present study to contain both dualtropic and ecotropic murine leukemia virus (mlv). the fibroblasts from individuals with manifest ac (22 subjects) and manifest pj (5 subjects) were up to 5 times more susceptible to transformation by rat 78ai-msv(ml ... | 1980 | 6268477 |
| antitumor effects of doxorubicin against a virally-induced rat osteosarcoma with minimal immunosuppression. | intratibial inoculation of a moloney strain of murine sarcoma virus (msv-m) in neonatal wistar-lewis rats produced osteosarcoma in 96% of animals and resulted in a median survival of 20 days. intraperitoneal (i.p.) administration of doxorubicin (adriamycin) (1-2 mg/kg/d, on day 10-12) resulted in reduced tumor growth and prolonged median survival to 95+ and 64 days, respectively. higher dose doxorubicin (3-4 mg/kg/d, on day 10-12) caused early lethal toxicity. autopsy data revealed a characteris ... | 1980 | 6937562 |
| experimental osteosarcoma in the mouse, induced by moloney's murine sarcoma virus. | the writers report an experimental trial on the mouse, consisting in the induction of osteosarcoma by inoculation of moloney's murine sarcoma virus (msv-m) into the proximal metaphysis of the tibia. this experiment was conducted on 90 balb/c female mice aged twenty-one days and of mean weight 12.8 g. one group of animals was also given immunodepressive drugs. the tumour developed in 100 per cent of cases, producing metastases in some of the animals and resulting in death in three cases. the radi ... | 1980 | 6938501 |
| non-t-cell-mediated cytotoxicity in msv tumor-bearing mice. iii. macrophage-mediated cytotoxicity against autochthonous msv tumor-isolated target cells. | cytotoxic macrophages have been isolated from moloney sarcoma virus (msv) tumors induced in uncompromised, immunosuppressed and athymic nude mice. macrophages from compromised mice were at least as active as those from uncompromised mice when tested against the autochthonous msv target cells. although both cytolytic and cytostatic activity could be demonstrated with all tumor-derived macrophages, cytostatic and cytolytic effects could be distinguished from each other only at high effector target ... | 1980 | 6966262 |
| progressing moloney sarcoma virus (m-msv) induced tumors: effect of host's immunomanipulation. | 1980 | 6970620 | |
| characterization of the presumptive sarcoma cells in primary msv tumors. | presumptive sarcoma cells have been isolated from primary msv tumors induced in normal, immunosuppressed (alg) and athymic nude mice. these cells were atypical in appearance, induced tumors in secondary hosts and expressed the viral antigens gp70, p30 and p12. in vitro growth characteristics of the msv cells were tested in a variety of assays defining cell transformation. none of these indicated that the virus-positive cells were transformed. sex chromosome marker studies were carried out to det ... | 1980 | 6989765 |
| immunotoxicology studies of sodium arsenate-effects of exposure on tumor growth and cell-mediated tumor immunity. | exposure of mice to sodium arsenate (na2has04) at levels of 2.5, 25 and 100 ppm as in the drinking water for 10-12 weeks increased the latent period and decreased the incidence of tumors induced by injection of msb sarcoma cells. tumor growth and regression induced by moloney sarcoma virus (msv) was not significantly affected by arsenic exposure. cell mediated tumor immunity was either unaffected or enhanced by exposure to arsenic. our results indicate that chronic exposure to sodium arsenate at ... | 1980 | 7217861 |
| activation of the transforming potential of a normal cell sequence: a molecular model for oncogenesis. | the molecularly cloned, long terminal repeat (ltr) of the moloney sarcoma virus (m-msv) provirus has been covalently linked to c-mos, the cellular homolog of the m-msv-specific sequence, v-mos. these newly constructed clones lack any m-msv-derived sequences other than the ltr, but in dna transfection assays they transform cells as efficiently as cloned subgenomic m-msv fragments containing both v-mos and ltr. cells transformed by ltr:c-mos hybrid molecules contain additional copies of mos dna, a ... | 1981 | 7233190 |
| electro-extraction of viruses from infected plant tissue. | an apparatus is described which was used for rapid extraction of viruses from frozen and thawed infected plant tissues. the novel principle is the establishment of a potential gradient of 15 to 20 volts/cm at approximately 90 degrees across the leaves of the infected plant while the leaves are surrounded by buffer of low molarity and of the appropriate hydrogen ion concentration. to keep the leaves in the correct orientation they were placed as single layers between coarse rigid plastic gauze. t ... | 1981 | 7255358 |
| distribution of in vitro-stimulated immune lymphocytes in mice bearing moloney murine sarcoma virus-induced primary tumor. | the distribution of in vitro-stimulated immune lymphocytes in tumor-bearing mice was studied. spleen cells from balb/c mice which had regressed moloney murine sarcoma virus (m-msv)-induced primary tumors, were sensitized in vitro by using moloney murine leukemia virus-induced balb/c lymphoma (lstra). lymphocytes obtained 6 days after stimulation were examined for cytotoxic activity against lstra cells, labeled with 51 cr or 99mtc, and inoculated into mice bearing msv-induced primary tumors. the ... | 1981 | 7274651 |
| platelet-derived growth factor (pdgf) enhances the growth of moloney sarcoma virus-induced tumors in mice. | the intramuscular (i.m.) administration of bovine or human platelet derived growth factor (pdgf) had a marked potentiating effect on the growth of moloney sarcoma virus (msv)-induced tumors in balb/c mice. pdgf had the tumor-promoting-activity when administered i.m. on the side of inoculation of msv two days after the virus, and subsequently every second day for 2-3 weeks. the extent of msv-induced tumor promoting activity of pdgf was age and sex-related. in view of the recently described antago ... | 1981 | 7332446 |
| in vitro demonstration of in situ autologous tumour-cell cytotoxicity in msv-induced tumours in a/sn mice. | moloney sarcoma-virus (msv)-induced tumours in a/sn mice have been dispersed with collagenase and dnase 8-15 days after virus inoculation, and both "sarcoma" and inflammatory cells separated by sedimentation velocity and adherence techniques. the isolated "sarcoma" cells had the morphological characteristics of atypical cells (i.e. cytoplasmic blebbing, vacuolization and prominent nucleoli) and were easily adapted to in vitro growth. as few as 2 x 10(3) of these cells inoculated i.m. produced ne ... | 1981 | 7053211 |
| t cell recognition of moloney sarcoma virus proteins. ii. phenotypes of the different lymphocyte subpopulations producing and responding to blastogenic factors and their relative frequencies during tumor regression. | the characteristics of the blastogenic response of splenic lymphocytes from molv/msv immune mice was examined. splenic lymphocytes from immune mice proliferate in vitro in response to the major virion envelope glycoprotein, gp70. associated with this response is production of blastogenic factors that induce the proliferation of nylon wool-purified lymphocytes from either normal or immune mice. the phenotype of antigen-specific lymphocytes essential for the production of blastogenic factors was f ... | 1981 | 6972414 |
| quantitation and clonal isolation of cytolytic t lymphocyte precursors selectively infiltrating murine sarcoma virus-induced tumors. | a limiting dilution mixed leukocyte-tumor cell microculture system was used to quantitate cytolytic t lymphocytes and their precursors (ctl-p), which infiltrate tumors induced by injection of moloney sarcoma-leukemia virus (msv-molv) complex into c57bl/6 mice. leukocyte populations obtained from tumors collected on day 10 after virus injection were found to contain significantly higher frequencies of operationally defined (tumor-specific) ctl-p than either peripheral blood leukocytes (pbl) or sp ... | 1981 | 6973602 |
| t lymphocyte tolerance and early appearance of virus-induced cell surface antigens in moloney-murine leukemia virus neonatally injected mice. | regression of moloney-murine sarcoma virus- (m-msv) induced sarcomas in normal adult mice is accompanied by generation of virus-specific cytotoxic t lymphocytes (ctl). however, when neonatal mice that were injected with moloney-murine leukemia virus (m-mulv carrier) were subsequently challenged as adults with m-msv, the sarcomas did not regress nor did they generate ctl. this failure to produce ctl cannot be ascribed to nonspecific immunodepressive effects or to suppressor cell generation since ... | 1981 | 6969741 |
| virally induced periosteal osteogenesis in mice. | inoculation of moloney murine sarcoma virus (m-msv) into shank muscles of adult nmri mice resulted in localized sarcoma and periosteal membrane proliferation with subsequent periosteal bone formation. newly formed bone arose from outer surface of shank bones. two weeks after m-msv inoculation the width of bone cortex increased nearly 4 times. the spaces between newly formed bone ossicles were filled with bone marrow. in the later stages these bone marrow cavities were merged with medullar caviti ... | 1981 | 6783270 |
| complementary dna copies of leukemia and sarcoma virus rna contain sequences of deoxycytidylate and deoxyguanylate. | single-stranded complementary dna (cdna) of the rna of gazdar murine sarcoma virus, gz-msv/mulv; moloney murine leukemia virus, m-mulv; mouse mammary tumor virus, mmtv; and simian sarcoma virus, ssv-1, were synthesized in endogenous reverse transcriptase reaction. gz-msv/mulv cdna was also synthesized in exogenous in vitro reverse transcriptase reactions. in the endogenous reaction, 30-35s, or 6.0- to 7.9-kilobase-length cdna transcripts were synthesized in high yield. in comparison, transcripts ... | 1981 | 6299564 |
| t cell-mediated immunity to oncornavirus-induced tumors. iii. specific and nonspecific suppression in tumor-bearing mice. | a strong cell-mediated immune response against friend, moloney, rauscher virus-induced (fmr) cell surface antigens has been demonstrated previously in mice which reject oncornavirus-induced tumors. in order to identify an eventual suppressor mechanism in animals with progressively growing tumors, experiments were initiated in c57bl/6 mice bearing either a murine sarcoma virus (msv) tumor or moloney virus-induced lymphoma (mbl2). progressive tumor growth was induced (a) in viremic animals first i ... | 1981 | 6452278 |
| t cell-mediated immunity to oncornavirus-induced tumors. iv. preliminary evidence for a specific suppression of anti-moloney cell-mediated immune response by autoimmune t cells. | previous reports have demonstrated that adult c57bl/6 mice infected with murine sarcoma virus (msv) develop a strong cell-mediated immune response against friend, moloney, rauscher virus-induced type-specific (fmr) antigens and reject their tumors. to demonstrate a possible role for auto-anti-msv t blasts, syngeneic c57bl/6 mice were immunized with highly enriched anti-fmr cytolytic t cells. one of 3 pools of these autoimmune t cells prepared from 12 surviving immunized mice (a) inhibited specif ... | 1981 | 6452279 |
| systemic and in situ natural killer and suppressor cell activities in mice bearing progressively growing murine sarcoma-virus-induced tumors. | the activity of systemic and in situ natural killer (nk) cells was measured in 3- to 5-week-old cba mice with progressively growing murine sarcoma virus (msv)-induced tumors. splenic nk activity was depressed in tumor-bearing mice. nk activity was quite low or not detectable in unfractionated cell suspensions from the tumors 10-12 days after inoculation of virus, but activity was observed upon depletion of phagocytic and/or adherent cells. to determine whether this in situ inhibition of nk activ ... | 1981 | 6457000 |
| neoplastic transformation of mouse fibroblasts by murine sarcoma virus: a multi-step process. | infection of cultures of three different normal rodent cell lines with murine sarcoma virus (msv) resulted in very rapid loss of contact inhibition of growth and morphological transformation. in the case of two of these lines, anchorage dependence of growth was also rapidly lost but with the 3rd, c3h10t1/2 c1.8, an established line of mouse embryo fibroblasts, there was a delay of many cell generations before the cells became anchorage independent. this was despite 100% successful infection, as ... | 1981 | 6268740 |
| mechanisms of kirsten murine sarcoma virus transformation-induced changes in the collagen phenotype and synthetic rate of balb 3t3 cells. | specific viral transformation rather than cell selection can explain the previously observed increase in the proportion of type iii procollagen compared to type i procollagen in balb 3t3 cells transformed by kirsten murine sarcoma virus (ki-msv). two subclones of balb 3t3 a31 were productively infected with with a temperature-sensitive ki-msv in the presence of helper murine leukemia virus (mlv), resulting in virtually complete transformation of cultures and eliminating selection of transformed ... | 1981 | 6273840 |
| structural organization and biological activity of molecular clones of the integrated genome of a balb/c mouse sarcoma virus. | balb/c mouse sarcoma virus (balb-msv) is a spontaneously occurring transforming retrovirus of mouse origin. the integrated form of the viral genome was cloned from the dna of a balb-msv-transformed nonproducer nrk cell line in the charon 9 strain of bacteriophage lambda. in transfection assays, the 19-kilobase-pair (kbp) recombinant dna clone transformed nih/3t3 mouse cells with an efficiency of 3 x 10(4) focus-forming units per pmol. such transformants possessed typical balb-msv morphology and ... | 1981 | 6275097 |
| properties of a sarcoma-growth-factor-like peptide from cells transformed by a temperature-sensitive sarcoma virus. | serum-free conditioned media was collected from three sarcoma virus-transformed cell lines and an untransformed cell line. all three virally transformed lines produced and released growth factors into their serum-free media. the major activity in all cases, whether the cells were transformed by moloney sarcoma virus (msv) or kirsten sarcoma virus (kisv), or whether they were mouse or rat, was a sarcoma-growth-factor (sgf)-like activity with an apparent molecular weight of 10,000. the sgf-like po ... | 1981 | 6276416 |
| translational products of moloney murine sarcoma virus rna: identification of proteins encoded by the murine sarcoma virus src gene. | in vitro translation of virion rna of moloney murine sarcoma virus (msv) strain 124 yielded major products having molecular weights of 63,000 (63k), 43k, 40k, 31k, and 24k daltons. a molecularly cloned subgenomic fragment of moloney msv comprised of the cellular insertion (src) region was utilized in hybridization arrest translation as a means of identifying products of the msv src gene. msv src dna specifically inhibited synthesis of the 43k, 40k, 31k, and 24k proteins, implying that each of th ... | 1981 | 6264137 |
| analysis of the myeloproliferative sarcoma virus genome: limited changes in the prototype lead to altered target cell specificity. | the myeloproliferative sarcoma virus (mpsv) derived from moloney sarcoma virus (msv-mol) is a unique sarcoma virus which causes expansion of the hematopoietic stem cell compartment as well as the erythroid and myeloid cell lineages. mpsv also induces spleen focus formation in adult mice as do friend and rauscher viruses. analysis of the mpsv genome on methyl mercury gels showed that the genome size is 7.0 kilobases, which is larger than the defective genome of any known msv-mol isolate. hybridiz ... | 1981 | 6264165 |
| alterations in growth requirements of kidney epithelial cells in defined medium associated with malignant transformation. | the possibility has been investigated that 1) the supplements required for the growth of the madin darby canine kidney (mdck) cell line in serum-free medium k-1 are indeed requirements for the growth of normal kidney cells in vitro, and 2) that alterations in these growth requirements are associated with malignant transformation. consistent with the hypothesis that mdck cells resemble normal kidney cells in culture, primary cultures of baby mouse kidney epithelial cells grow in medium k-1 and re ... | 1981 | 6265706 |
| host range of murine sarcoma virus, its host modification and phenotypic mixing with endogenous virus. | the m(msv)ag-50 cells produce competent ecotropic sarcoma virus which is able to transform several rodent embryo cells and replicate in them. the expanded host range has shown that the virus acquired some host information which facilitate the transformation of heterologous cells. the transformed cells were xc positive and with transformed phenotype in vitro. the genome of mouse sarcoma virus from nonproducer rat liver cells could be rescued by xenotropic endogenous virus. the obtained virus has ... | 1981 | 6265817 |
| interferon effect on collagen and fibronectin distribution in the extracellular matrix of murine sarcoma virus-transformed cells. | the transformation of murine balb/c embryonic fibroblasts by murine sarcoma virus, moloney strain, followed by prolonged treatment with murine interferon, resulted in the appearance of a new cell population (msv-if+). these msv-if+ cells are characterized by the recovery of a normal phenotype, contact inhibition, and lack of colony formation in agar. this phenotypic change of the msv-if+ cells is associated to the neosynthesis of a dense fibrous matrix beyond the cell periphery. ultrastructural ... | 1981 | 6167350 |
| further studies on anti-tumor activity of adenovirus fibre protein on murine sarcoma tumours. | the present study demonstrates that subcutaneous injection of purified adenovirus 12 fibre protein (fp) to 4-week-old balb/c mice, 4, 2 and 1 day(s) before intramuscular injection of murine sarcoma virus (msv-m) or 2 and 1 day before and 1 day after msv-m injection causes significant inhibition of tumour growth (p less than 0.001). the evidence suggests that treatment with fp leading to tumour inhibition is due to neither an interferon mechanism nor to inhibition of virus multiplication of fp in ... | 1981 | 6169787 |
| complete nucleotide sequence and organization of the moloney murine sarcoma virus genome. | the complete nucleotide sequence of a mammalian transforming retrovirus. moloney murine sarcoma virus, has been determined. msv, recombinant virus derived of helper viral and cellular sequences, possesses termini resembling prokaryotic transposable elements. the viral genome has the coding capacity for the moloney murine leukemia virus gag gene product and contains large deletions in pol and env genes. a large open reading frame encompassing its cell-derived sequences codes for its putative tran ... | 1981 | 6170110 |
| rapid syncytium formation induced by moloney murine sarcoma virus in 3t3/nih cells and its delay by mouse interferon. | moloney murine sarcoma virus (msv) clone 124 was found to induce rapid syncytium formation upon infection of 3t3/nih at a high multiplicity of infection. this effect became apparent, by light microscopy, within 1 to 2 hours, whereas by scanning electron microscopy, clusters of 4 to 25 cells were seen in their initial steps of syncytium formation within 20 to 30 minutes after virus addition. it appeared that the cell fusion was initiated by connection between the cells through virus bound to thei ... | 1981 | 6174107 |
| use of hybridoma-resident variant cell lines to study h-2db/fmr-specific cytotoxic t cells. | an h-2db heterozygous tumor cell line and a variant subclone bearing a mutant gene product were used to analyze the h-2db specificity of cytotoxic t lymphocytes (ctl) generated during a moloney murine sarcoma virus (msv) infection. when the mutant cells were used as targets for msv-specific ctl, the amount of cell lysis, compared with that seen with the nonmutant parental cells, was drastically decreased. however, cells of the mutant clones remained susceptible to allogeneic ctl specific for the ... | 1981 | 6174439 |
| reorganization of the cytoskeleton by interferon in msv-transformed cells. | beta and gamma interferons were found to enhance the organization of microfilaments, intermediate filaments, and fibronectin in the murine sarcoma virus (msv)-transformed cell line. furthermore, both interferons increased the number of intermediate-type junctions. sodium butyrate was also found to act in a similar way and, when associated with interferon, an additive effect was observed. in the cell line, cultured for many passages in the presence of beta interferon (msv-if+), the cytoskeletal n ... | 1981 | 6180063 |
| viral-versus non-viral-induced yolk sac tumors in the rat. | yolk sac tumors were induced in fetectomized rats by displacement of the visceral yolk sac outside the uterus with or without injection of murine sarcoma virus (msv) into the placenta. some of the animals were immunized with msv prior to surgery. the biological, morphological and immunological characteristics of the tumors which develop in animals either injected or not with virus are compared. the results indicate that msv inoculation into the placenta increases the tumor incidence, shortens th ... | 1982 | 6181488 |
| effect of mouse interferon on cell transformation and virus production in rat cells exogenously infected with moloney murine sarcoma and leukemia viruses. | foci of transformed cells, produced by msv(124), appeared to result only from the primary infection, since this virus stock yielded a virus-nonproducing infection. on the other hand, the majority of foci scored in msv/mlv-infected cultures, were generated by multiple secondary infections with the progenies of the primary infection. mouse interferon (if) was highly inhibitory for cell transformation by both virus stocks. however, this inhibition was apparent in msv(124) infected cultures only if ... | 1982 | 6177647 |
| activation of sv40 genome by 72-base pair tandem repeats of moloney sarcoma virus. | the simian virus 40 (sv40) 72-base pair (bp) tandem-repeated sequences have a crucial role as an activator element in viral gene expression. we replaced the sv40 72-bp repeat with a 72-bp repeat derived from the long terminal repeat (ltr) of cloned moloney murine sarcoma virus (msv) dna. although there is no detectable sequence homology to sv40, the msv repeats can substitute functionally for the sv40 repeats and generate a viable virus in monkey kidney cells. | 1982 | 6276775 |
| pericellular matrix and cell surface glycoproteins of virus-transformed mouse epithelial cells. | mouse embryo mus musculus castaneous epithelial cells, transformed with moloney murine sarcoma virus (msv) or with ecotropic murine leukemia virus (mulv), were analyzed for production of pericellular matrix glycoproteins. the nontransformed, msv-transformed, and mulv-transformed cells produced fibronectin, laminin, type i collagen, and small amounts of type iii collagen when studied by immunofluorescence using specific antibodies. the virus-transformed epithelial cells produced enhanced amounts ... | 1982 | 6277476 |
| moloney murine leukemia virus-induced tumors: recombinant proviruses in active chromatin regions. | the dnase i sensitivity of chromosomal dna regions carrying integrated proviral genomes of moloney (m-mulv) and akr murine leukemia virus (akr-mulv), and the cellular homologue of the mos-gene (c-mos) of moloney sarcoma virus (msv) were studied in tumor tissues of leukemic mice. the genetically transmitted sequences of m-mulv, akr-mulv, and the c-mos gene are all in dnase i resistant chromatin conformations in m-mulv-induced tumors. each m-mulv-induced tumor contained at least one somatically ac ... | 1982 | 6278422 |
| receptor-associated changes of the catecholamine-sensitive adenylate cyclase in glioma cells doubly transformed with moloney sarcoma virus. | a doubly transformed rat glioma cell line, designated c6v-1, was obtained from rat glioma c6 cells by infection with a rat-adapted variant of moloney sarcoma virus (msv-m-os). the c6v-1 cells show karyotypic changes in chromosome number (43) and structure, while c6 cells possess a normal male karyotype. c6v-1 and c6 cells were employed for characterization of a receptor-adenylate cyclase system of the surface membrane. c6v-1 cells showed lower adenylate cyclase activity than that of c6 cells, th ... | 1982 | 6279681 |
| human nucleotide sequences related to the transforming gene of a murine sarcoma virus: studies with cloned viral and cellular dnas. | a recombinant plasmid, pi26, has been constructed by cloning into pbr322 a transforming gene of murine sarcoma virus (a moloney strain, clone 124, msv) synthesized by detergent-treated virions. from this plasmid a xbai-hindiii fragment has been isolated which contains only mos-specific sequences. this mos-specific probe has been used for screening a human gene library cloned in bacteriophage lambda charon 4a. of these, 19 clones have been isolated containing mos-related sequences. by physical ma ... | 1982 | 6281133 |
| a generalized method of subcloning dna fragments by restriction site reconstruction: application to sequencing the amino-terminal coding region of the transforming gene of gazdar murine sarcoma virus. | the technique of restriction site reconstruction was generalized so as to allow the subcloning of any dna fragment and its subsequent reexcision with ecori, xbai, xhoi or hindiii. after excision, the 3' terminus of each strand will be derived from the starting nucleic acid, permitting the use of such fragments as primers for nucleotide sequencing by primer extension methods. the technique was used to subclone a 56 base pair bstni-ddei fragment of moloney murine sarcoma virus (mo-msv) as a unique ... | 1982 | 6281735 |
| candidate product of the fbj murine osteosarcoma virus oncogene: characterization of a 55,000-dalton phosphoprotein. | sera from rat bearing tumors induced by inoculation of fbj murine osteogenic sarcoma virus (fbj-msv) nonproducer rat cells precipitate two proteins with molecular weights of 55,000 (p55) and 39,000 (p39) from fbj-msv-transformed cells. these proteins cannot be precipitated from uninfected cells or cells transformed by other strains of murine sarcoma virus, nor can they be precipitated by sera specific for the viral structural proteins. a methionine tryptic peptide mapping analysis showed that p5 ... | 1982 | 6283132 |
| t24 human bladder carcinoma oncogene is an activated form of the normal human homologue of balb- and harvey-msv transforming genes. | a transforming gene isolated from t24 human bladder carcinoma cells is closely related to the balb murine sarcoma virus (msv) onc gene (v-bas). this transforming gene is localized to a 4.6 kilobase pair (kbp) region and is expressed as a 1.2-kbp polyadenylated transcript, which contains v-bas related sequences. moreover, antisera known to detect the immunologically related onc gene products of balb- and harvey-msvs recognized elevated levels of a related protein in t24 cells. the normal human ho ... | 1982 | 6283384 |
| balb- and harvey-murine sarcoma virus transformation of a novel lymphoid progenitor cell. | balb- and harvey-murine sarcoma viruses (msv) comprise a family of retroviruses whose mouse- and rat-derived onc genes are closely related. these viruses induce sarcomas and erythroleukemias in susceptible animals. an in vitro colony assay that detects transformation of lymphoid cells by abelson-murine leukemia virus was used to demonstrate that balb- and harvey-msv transform a novel hematopoietic cell both in culture and in vivo. bone marrow colony formation was sarcoma virus dependent, followe ... | 1982 | 6286838 |
| murine xenotropic type c viruses. iv. replication and pathogenesis of ducks. | the xenotropic (x-tropic) mouse type c virus (mulv) and its pseudotype of murine sarcoma virus (msv) were inoculated into several fertilized developing pekin duck eggs. the development of the duck embryos was substantially reduced in those receiving the x-tropic viruses compared to eggs inoculated only with tissue culture medium. infections virus was isolated from some of the adult animals; in others, evidence for integrated virus sequences in the tissues was noted. no specific pathology was fou ... | 1982 | 6288852 |
| characterization of xenotropic and dual-tropic type c retroviruses isolated from abelson tumour. | tumours induced in balb/c mice by abelson virus complex were found to contain a xenotropic virus (a-x-mulv) and an nb-tropic, dual-tropic virus (nbx), in addition to the moloney leukaemia virus (m-mulv) and the defective, transforming abelson virus genome. both a-x-mulv and nbx virus were presumably present in a genomically masked form and could be recovered only by co-cultivation of tumour cells with permissive cells. only about 0.87% and 0.13% of the viruses in the co-culture supernatant repre ... | 1982 | 6292337 |
| fbj murine osteosarcoma virus: identification and molecular cloning of biologically active proviral dna. | a 12.0-kilobase ecori restriction fragment containing fbj murine osteosarcoma virus (fbj-msv) proviral dna was identified in fbj-msv-transformed nonproducer rat cells and molecularly cloned in bacteriophage charon 30 (lambda fbj-1). a 5.8-kb hindiii fragment containing the entire fbj-msv proviral dna was isolated from lambda fbj-1 and subsequently subcloned in plasmid pbr322 (pfbj-2). the dna from recombinant plasmid pfbj-2 was able to induce morphological transformation of rat fibroblasts in ti ... | 1982 | 6292525 |